This invention relates to machines for assembling coil springs by connecting them with elongated helical wire coils, as for mattresses, and more particularly to an improvement on the machine disclosed in U.S. Pat. No. 3,334,664 to Wojahn.
Assembly machines of the type in the Wojahn patent operate effectively, but have certain disadvantages. One is that there are significant waste helical coil portions cut off the tail end of each of the two helical coils for each row of springs assembled. That is, each helical coil must be made several inches longer than the rows of springs so that the trailing end will remain in the conventional upper and lower feed-in rolls, in order to drive the leading ends of the helical coils to the far end of the rows of springs. These several inch long portions must then be cut from each helical coil as waste. Another disadvantage of existing machines relates to the clinching and cutting for the ends of the helical coil. In some machines, the operators must twist the helical coils by hand to clinch the ends. While machines as in U.S. Pat. No. 3,648,737 provide mechanical clinching using a rotational clincher, and cutting with a reciprocating knife, an improved mechanism is needed.